31129489 has 4 divisors (see below), whose sum is σ = 31327924. Its totient is φ = 30931056.

The previous prime is 31129481. The next prime is 31129517. The reversal of 31129489 is 98492113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98492113 = 37 ⋅2661949.

It can be written as a sum of positive squares in 2 ways, for example, as 4915089 + 26214400 = 2217^2 + 5120^2 .

It is a cyclic number.

It is not a de Polignac number, because 31129489 - 2³ = 31129481 is a prime.

It is a super-2 number, since 2×31129489² = 1938090170802242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31129481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98982 + ... + 99295.

It is an arithmetic number, because the mean of its divisors is an integer number (7831981).

Almost surely, 2^31129489 is an apocalyptic number.

It is an amenable number.

31129489 is a deficient number, since it is larger than the sum of its proper divisors (198435).

31129489 is a wasteful number, since it uses less digits than its factorization.

31129489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198434.

The product of its digits is 15552, while the sum is 37.

The square root of 31129489 is about 5579.3807004004. The cubic root of 31129489 is about 314.5748492992.

The spelling of 31129489 in words is "thirty-one million, one hundred twenty-nine thousand, four hundred eighty-nine".